Laser Lidar Technology: A Revolutionary Application on Ten-zan's Northern Slope
Recently, a significant milestone was achieved in the field of lidar technology with the successful completion of a large-scale project on the northern slope of Ten-zan. This project, a joint venture between the Xinjiang First Surveying and Mapping Institute and the Second Surveying and Mapping Institute, marked the first time high-precision lidar point cloud data was obtained over a large area.
High-Precision Lidar Point Cloud Data
The process of obtaining high-precision lidar point cloud data involves transmitting laser signals to the ground using airborne lidar technology. The reflected laser signals from the ground are then collected, providing high-precision 3D position information of ground points. This data is crucial in the creation of a Digital Elevation Model (DEM), which focuses on the topographical features of the Earth's surface, such as mountains and rivers.
Digital Elevation Model and Digital Surface Model
The 2-meter grid digital elevation model and the digital surface model not only realize the digital expression of three-dimensional topography but also provide relevant industries with a three-dimensional terrain database and analysis basis. This improves the current situation and accuracy of natural geographical elements in Xinjiang, providing basic data resources for Xinjiang's digital construction.
The Importance of Grid Size in DEM
"The smaller the grid, the smaller the area represented by each grid, and the higher the spatial resolution and accuracy of the digital elevation model," said Wang Jing, deputy director of the Fifth Branch of the Second Surveying and Mapping Institute of the Autonomous Region. Traditional DEM data production mainly adopts the digital photogrammetry method, with a grid distance of 5 meters. However, this project uses lidar technology to obtain point cloud data with a density of not less than 1 point per square meter. Each pixel in the DEM represents an area of 2 meters × 2 meters above the ground, providing richer and more accurate data information.
Project Implementation
The project was organized and implemented in two phases. The first phase utilized advanced airborne lidar scanners to acquire surface-intensive point cloud data. The second stage used data processing software to produce digital results through steps such as point cloud filtering, classification, and interactive editing.
By focusing on lidar technology and its application in creating a digital elevation model and digital surface model, this article aims to inform readers about the latest advancements in this field and their impact on the digital construction of Xinjiang.
